62results about How to "Can be stored for a long time" patented technology

The invention belongs to the field of thermal batteries, and relate to a carbon coated thermal battery electrode material and a preparation method thereof. Glucose and other carbon sources are added in the process of preparing cobalt disulfide through a hydrothermal method, and the cobalt disulfide electrode material with a carbon coated structure is prepared in situ; the mass content of carbon in the obtained material relative to cobalt disulfide ranges from 1% to 25%. The electrode material has the advantages of being high in specific capacity, good in air stability, simple in preparation process, easy to prepare in a large scale and the like.

The invention discloses a method for analyzing ferrosilicon alloy components for X-ray fluorescence spectrum analysis. A method for preparing a sample comprises the following steps of: selecting a proper oxidant; adding a flux into a platinum crucible, putting the platinum crucible in a high temperature furnace, and melting the flux at high temperature to manufacture a wall built-up flux crucible with the basement of flux; mixing a ferrosilicon alloy test sample, the flux and the oxidant, pouring the mixture into the flux crucible, and covering a certain amount of mixed flux; and putting the flux crucible filled with the ferrosilicon alloy test sample, the flux, the oxidant and the mixed flux into the high temperature furnace, preliminarily oxidizing at low temperature, shifting into a high temperature zone, and melting at high temperature to prepare the ferrosilicon alloy test sample glass sample for the X-ray fluorescence spectrum analysis. In the technical scheme, elements are uniformly distributed in the prepared glass sample, and the glass sample has no particle effect and can be preserved for a long time; moreover, the operation method is simple and safe, the preparation time of the sample is short, and primary and secondary quantity elements in the ferrosilicon alloy are rapidly and accurately measured.

The invention discloses a method for preparing a linear polyurethane phase change material. The method comprises the following steps: dissolving polyethylene glycol and diisocyanate into solvent in inert atmosphere, reacting in the presence of optional catalyst, adding tertiary amine type chain extender containing hydroxyl for chain extension, adding an optional neutralizer for salt formation so as to obtain the linear polyurethane phase change material, wherein the molar ratio of the sum of hydroxyl of polyethylene glycol and hydroxyl of chain extender to the isocyanate group of diisocyanate is 1:1, the add amount of the catalyst accounts for 0-1% the total weight of the polyethylene glycol, diisocyanate and chain extender, the molar ratio of neutralizer to tertiary amine type chain extender is 0-1, and the molecular weight of the polyethylene glycol is higher than 2000. The linear polyurethane phase change material prepared by the method has a linear structure and large enthalpy of phase change, has a simple preparation method, is low in cost, has stable property, can be stored for long time, is not solidified and cross-linked, is easy to process and shape, and is beneficial to large-scale popularization and application.

The invention belongs to the technical field of thermal transfer printing materials and particularly relates to a laser thermal transfer ribbon. The laser thermal transfer ribbon is formed by a base film, a separating layer, a laser imaging layer and an ink coating layer. Water or alcohol or a mixed solvent is added to a waterborne releasing agent or a resin releasing agent or a waxiness releasing agent to form the separating layer. The laser imaging layer is composed of hydroxyl acrylic resin, celluosic resin, isocyanate, additives and a mixed solvent. The ink coating layer is composed of acrylic resin, chloride ether resin, rosin resin, petroleum resin, pigments, additives and a mixed solvent. The laser thermal transfer ribbon is clear in transferred character and image, good in adhesive force, resistant in friction, poaching-proof, aging-resistant, resistant in high-low temperature, suitable for wide transfer base materials and transfer temperature, and capable of meeting transfer demands of high speed and high efficiency. The laser thermal transfer ribbon enables a product to be bright, colorful, exquisite and gorgeous, improves product levels, has a certain anti-fake function, and improves product market compatibility.

The invention discloses a new method for surveying population density of microarthropods such as panonychus citri mcgregor, predatory mites and diaphorina citri kuwayama. The new method comprises the following steps of: randomly drawing a citrus sample plant; placing adhesive plate boxes below tree crowns in the east, south, west and north directions of the tree crown of the citrus sample plant; knocking branches of the tree crowns above the positions where the adhesive plate boxes are arranged for many times to drop the microarthropods; adhering the microarthropods falling in the adhesive plate boxes to adhesive plates of the adhesive plate boxes; collecting the adhesive plate boxes to perform statistical survey, wherein the adhesive plate boxes comprise box bodies; a layer of plate corresponding to the size of the bottom surface is arranged on the bottom surface of each box body; an adhesive material is coated on the upper surface of the plate; and thus, the adhesive plates are constructed. Thus, by surveying with the method provided by the invention, the used time is less, the sample can be stored for a long time, and most importantly, the detection sensitivity to the microarthropods of red spiders, predatory mites and the like is greatly improved; and since the detected objects are adhered and cannot escape, the detection is more convenient, simpler and more accurate.

The invention relates to a method for preparing 5-(2-methylmercapto-ethyl)-hydantoin by utilizing crude hydrocyanic acid gas and relates to the field of chemical industry. The method disclosed by the invention comprises the following steps of: completely reacting hydrocyanic acid mixed gas made by adopting an Ann method with methylmercapto propionaldehyde to obtain a 2-hydroxyl-4-methylmercapto-butyronitrile reaction system under the catalytic action of organic alkali; and sufficiently reacting the 2-hydroxyl-4-methylmercapto-butyronitrile reaction system with ammonium bicarbonate in a water medium to obtain 5-(2-methylmercapto-ethyl)-hydantoin. Due to adoption of raw materials which are not rectified or purified, the method disclosed by the invention is short in production time, high in production efficiency and low in production cost; the prepared 2-hydroxyl-4-methylmercapto-butyronitrile reaction system is steady in property and can be stored for a long time; and 5-(2-methylmercapto-ethyl)-hydantoin with high purity and high yield can be obtained through simple separation and purification operations under the synergistic effect of other substances in reaction liquid.

The invention relates to a method for preparing chlorine dioxide decontaminated wet towel, which comprises that first building one state balance system in the chlorine dioxide water solution, adding some slow-release agent into the solution, restraining the volatilization and decomposition of chlorine dioxide, adding non-reducing essence and humectant into the solution, wetting the carrier with said solution, sealing with iridescent plastic bag or plastic box. The invention can effectively disinfect via wiping, without toxicity, with long storage time than one year and low cost.

The invention provides a synthetic method of a water medium dispersed cerium zirconium oxide nano material. The synthetic method comprises the following steps: (1) performing a precipitation reaction by using an inorganic salt aqueous solutios of Ce and Zr and an inorganic base aqueous solution of Ce and Zr to prepare a Ce-Zr mixed hydroxide precipitate; (2) heating and refluxing the Ce-Zr mixed hydroxide precipitate to prepare a Ce-Zr hydroxide cosolubilization body; (3) filtering and washing the Ce-Zr hydroxide cosolubilization body to prepare a Ce-Zr hydroxide hydrogel; (4) mixing the Ce-Zr hydroxide hydrogel with organic alcohol, organic acid and high polymer to prepare a Ce-Zr oxide synthetic sizing material; and (5) heating and further performing hydro-thermal synthesis on the Ce-Zr oxide synthetic sizing material to obtain the water medium dispersed cerium zirconium oxide nano material. The cerium zirconium oxide nano particles obtained by the method provided by the invention are single crystals, have a nano scale of 2-8nm, and are monodispersed in a water medium; and the mass of cerium zirconium oxide accounts for 5-10% of the sol body volume of the nano material.

The invention provides a ketoconazole foaming agent and a preparation method thereof, which are used for treating fungal infective diseases, such as seborrheic dermatitis and the like.

Disclosed is a process for preparing apple preserved fruit, which is characterized in that the process for preparing comprises <1> cleaning, separately cutting and pre-cooking apples; <2> cooking apples in sugar liquor charged with additives for 60-120 minutes according to weight proportion of 10:0.4-0.8 under temperature of 100 DEG C; <3> charging sugar liquor every 20-30 minutes according to weight proportion of 10:0.3-1.2 during the process of cooking; <4> fishing out apples to be dried and shaped; and <5> completing production after the cooling, ultraviolet disinfecting and packing. The process for preparing apple preserved fruit has the advantages that <1> the preparing art is simple and clean, <2> the product belongs to the pure-natural nourishing food, <3> the product is convenient for eating, with delicious taste, <4> the product keeps a plurality of nutriment contained in apples, which facilitates the product to be rich in nutrition, thereby promoting cerebra development, delaying memory declining and resisting caducity after long time eating, and <5> the transportation is convenient, and the product can be stored for a long time.

The invention discloses a fruit-vegetable sheet jelly and a preparation method thereof. The fruit-vegetable sheet jelly comprises the following raw materials in percentage by weight: 80.00 percent of water, 15.00 percent of potato powder, 4.73 percent of pea meal, 0.05 percent of konjaku flour, 0.03 percent of potassium chloride, 0.04 percent of carrageenan and 0.15 percent of vegetable juice. The preparation method comprises the following steps: I, burdening: preparing the needed raw materials according to a working formula; II, putting into water and blending: continuously stirring to prevent precipitates; III, filtering the precipitates out: filtering impurity particles through a fine filter screen; IV, filling and cooking; and V, cooling rapidly. According to the fruit-vegetable sheet jelly and the preparation method thereof, the conventional preparation method is improved, so that the use of food additives and the like which are harmful to human bodies is avoided. The fruit-vegetable sheet jelly prepared with the method has the advantages of no pigment, no additive, high nutrient value, high glossiness, high toughness, low possibility of frangibility and long shelf life.

The invention discloses an ammonium salt preparing method, which comprises the following steps: A, preparing ammonium salt aqueous solution with ammonium salt; B, adding 1-20%function integral and crossbridging integral in ammonium salt aqueous solution at the temperature between 10deg.c and 90deg.c; C, putting 5-30% initiating agent liquor in liquor of step (the admission amount is 0.1-1% function integral and crossbridging integral); getting the ammonium salt by polymerization reaction for one hour to five hours. The invention is characterized by the following: the raw material is easy to get; the manufacturing technique is simple; it's easy to operate; the prepared ammonium salt aquagel is stored in network architecture of function macromolecule with ammoniacal nitrogen fertilizer and water; It's widely used for horticulture cultivation and desert handing.

The invention discloses a theileria equi immunoblotting detecting method and a method for preparing a kit, wherein the theileria equi immunoblotting detecting method in the invention is established on the basis of acquiring diagnostic antigen and positive control serum via Cochlearia officinalis hyperoxide enzyme label and chemical light emitting prime. The solvent for the method in the inventionis little in amount, low in cost, high in specificity, high in sensitivity, high and fast in operation, free of toxicity and harm, low in required conditions, easy for judging the test result, long-time for storage, and stronger in specificity than ELISA. The method in the invention detects no false positive and false negative result.

The invention discloses a method for preparing injection-grade alpha-cyclodextrin. The method comprises the steps: preparing alpha-CGTase immobilized enzyme by adopting epoxy resin as a vector, preparing starch into starch milk, adding the alpha-CGTase immobilized enzyme for liquefying starch, reacting in a filled reactor filled with the alpha-CGTase immobilized enzyme, carrying out ultrafiltration on a conversion solution, and collecting dialysate; treating the dialysate by using alpha-amylase and saccharifying enzyme, decolorizing with activated carbon, concentrating by using reverse osmosis membrane, recrystallizing, filtrating to remove beta-cyclodextrin; and further concentrating mother liquor with a reverse osmosis membrane, crystallizing, filtrating, drying and grinding, thus obtaining the injection-grade alpha-cyclodextrin. According to the method, the prepared immobilized enzyme has the advantages that the stability is good, the immobilized enzyme can be reused; a product and a substrate can be seperated extremely easy, the utilization efficiency of enzymes is high, continuous operation and automated control can be carried out, the process is simple and convenient, the production cost is low; alpha-cyclodextrin is produced by adopting a solvent-free process, the production equipment is simple, the reaction conditions are mild, the energy consumption is low, and solvent residual contamination does not exist, so that the method is very environment-friendly and energy-saving.

The invention discloses the use of super hard gypsum in preparing analogue human alveolus bone. 1. Fixing alveolus bone hard plastic model in the center of model box. 2. Mixing silicon rubber A, B components. 3. Filling silicon rubber into model box on stirrer. 4. Hardening at room temperature. 5. Removing plastic model. 6. Mixing super hard gypsum with water into paste. 7 filling the paste into alveolus bone die. 8. Hardening at room temperature. 9. Removing gypsum model. 10. Drying at room temperature.

Theinvention discloses a carbon foam loaded magnesium-nickel-copper composite hydrogen storage material. The material is prepared from 50-70 parts by mass of carbon, 20-40 parts by mass of magnesium, 5-10 parts by mass of nickel, and 5-10 parts by mass of copper. The invention further discloses a preparation method of the carbon foam loaded magnesium-nickel-copper composite hydrogen storage material. The preparation method comprises the steps of preparing carbon foam carrier material particles, preparing magnesium-nickel-copper alloy powder, and preparing the hydrogen storage material with the prepared carbon foam carrier material particles and the prepared magnesium-nickel-copper alloy powder. Multiple metal alloys are loaded based on a skeleton and a mesh porous structure of the carbon foam, so that clear channels are provided for diffusion and absorption of gas in the hydrogen storage process. The formed composite material has performance of both the carbon foam and the multi-component alloy hydrogen storage material, thereby having high hydrogen storage capacity. The raw materials of the hydrogen storage material are from coal tar pitch and magnesium-nickel-copper alloy. The preparation process is simple and controllable, and the cost is low.

The invention discloses a wearable electrocardio detector. The wearable electrocardio detector comprises an electrocardio electrode piece used for making contact with the human body for leading; the electrocardio electrode piece is connected with an electrocardio single sensor which is worn on the human body and used for collecting electrocardiogram information; the electrocardio single sensor is connected with a microprocessor used for managing operation of the device and processing the information preliminarily; the microprocessor is further connected with an acceleration sensor which is worn on the human body and used for collecting motion information of the human body, and the microprocessor is connected with a wireless communication module which is worn on the human body and used for communication with the outside. According to the wearable electrocardio detector, electrocardiograms, motion tracks and other data of the human body are detected and collected through a sensor network technology, and the data are transmitted remotely in a wireless mode through a low-power-consumption wireless communication technology, data safety can be achieved through a cloud technology, the data can be stored for a long time, called and analyzed, and precise service can be provided according to different conditions of users.

The invention relates to a method for preparing a teaching specimen of a left ventricular outflow tract view of a fetus suffered from a congenital heart disease. In the method, a free heart specimen is prepared after a selected artificially-labored fetus having a malformed heart is antiseptically treated; and in the left ventricular outflow tract view, the horizontal axis of the view is parallel to the long axis of the heart by taking a pulmonary conus as a start point of a cross section, the cross section is up to a superior vena cava through aorta ascendens and down to the apex of the heart through an anterior interventricular groove. The obtained apical four-chamber view specimen has the advantages of integrated and complete structures of all parts, no damage to microstructures in the heart, the same shape as that in a real living body, and capability of meeting the requirements of medical teaching and practice and the like, and is suitable for schools, hospitals or medical research institutes.

A green and healthy laying duck feed comprises, by weight, 29.9-30.7% of corns, 15.7-19.5% of peanut kernel meal, 34.1-36.2% of wheat middling, 8-8.9% of stone powder, 1% of soybean oil, 2-8% of fermented mulberry leaves, 0.25% of methionine, 0.8% of calcium hydrogen phosphate, 0.24% of lysine, 0.21% of threonine, 0.05% of breeding chicken multi-vitamins, 0.05% of choline, 0.15% of composite trace elements, 0.33% of edible salt and 0.42% of maifan stones. The duck feed prepared by adding the fermented mulberry leaves can improve the grade and the egg yolk color of duck's eggs, improve the nutritional values of the duck's eggs and reduce the cholesterol content.

The invention relates to the field of residual pesticide detection, in particular to a kit for detecting residual thiophosphate organophosphorus pesticides and an application method of the kit.The kit comprises an extracting agent, a reducing agent, precursor liquid, a pH controlling agent, a dropper and a reaction tube; the reducing agent is a tyrosine methyl ester grafted hyaluronic acid aqueous solution of 2.4 ng/mL to 24 micrograms/mL.According to the kit for detecting the residual thiophosphate organophosphorus pesticides and the application method of the kit, the organophosphorus pesticides are added in the gold nanoparticle formation process, the three processes of gold nanoparticle formation and aggregation and protection layer establishment are synchronized, the aggregation degree of gold nanoparticles is controlled in the formation process of the gold nanoparticles, the surfaces of formed gold nanoparticle aggregates are provided with protection layers, the stability of the aggregates is greatly improved, the detection stability is improved, the detection result is not limited by the detection time any more, and repetition is easy.

The invention discloses a composite flowery microcapsule essence which comprises a capsule wall and a capsule core. The surface of the capsule core is coated with the capsule wall. The capsule wall ismade of polyurea resin. The capsule core is prepared from the following raw materials in percentage by mass; 11%-22% of oil soluble essence, 10.5%-17.5% of an emulsifying agent, 32%-57% of a co-emulsifier, 1%-3% of lilial, 2%-6% of citral, 0.5%-1% of B-position damascenone, 4%-10% of B-position ionone, 4%-8% of methyl cedar ketone, 1%-3% of ambrotone, 0.2%-1% of rose ether, 2%-5% of vanillin and5%-8% of crystalline rose. An existing preparation method is improved, all the raw materials of the capsule core can be fully and uniformly stirred through primary emulsification and secondary emulsification, and the prepared composite flowery microcapsule essence can be subjected to wall breaking to release unique rose fragrance under a friction force or a small external force, is good in compatibility, can be stored for a long time, and is green and pollution-free.

The invention belongs to the technical field of chemical agents for oil fields, and preparation thereof, and particularly relates to a thickened oil thermal production well sulfide removing agent anda preparation method thereof. The sulfide removing agent is formed by compounding epoxypropyl biimidazole with nitrate, and comprises, by mass, 10-20% of the epoxypropyl biimidazole, 5-10% of the nitrate, and the balance of water, and the epoxypropyl biimidazole is formed by reacting glyoxal, an ammonium salt solution (by ammonia) and epoxy chloropropane according to a molar ratio of 3:(4-5):(1-2). The sulfide removing agent can effectively remove hydrogen sulfide in an oil well, and also can effectively remove harmful sulfides such as methyl mercaptan, ethyl mercaptan and carbonyl sulfide; and the sulfide removing agent has a small dosage, and the dosage of the sulfide removing agent is 40% or above less than that of a triazine agent in the oil well shaft environment.

The invention provides grain pulp for improving the quality of sheep meat, relates to a sheep feed, and aims to solve the problems that the current sheep meat has poor quality, and landfill treatment of fresh citrus pulp causes resource waste and environmental pollution. The grain pulp consists of a main component and an auxiliary component, wherein the main component is citrus pulp; and the auxiliary component consists of urea, corn flour, molasses, sodium sulfate, zeolite, sodium dihydrogen phosphate and edible salt. By the grain pulp, the carcass net meat weight and pure meat percentage ofthe sheep can be remarkably improved, the muscle shearing force is reduced, the level of meat color is improved, the content of cholesterol in the sheep meat can be remarkably reduced, and the level of calcium is remarkably improved, so that the quality of sheep meat is remarkably improved; and the grain pulp has low cost, good palatability, high content of protein and balanced nitrogen-sulfur proportion and calcium-sulfur proportion, and has important significance for improving the economical benefit of sheep breeding and realizing sustainable circulation and efficient utilization of resources. The grain pulp has a wide prospect in the field of sheep feeds.

The invention discloses a method for preparing a cement-based piezoelectric composite material surface nickel electrode. The method comprises the following steps: roughening, reducing, activating, and plating nickel, wherein the step of roughening is implemented in an alkali roughening liquid; a used reduction solution is a methanol or ethanol solution of sodium borohydride; a used activating liquid is an aqueous solution of nickel acetate or nickel sulfate; a nickel plating liquid consists of 18-22g/L of nickel sulfate, 8-16g/L of trisodium citrate, 26-32g/L of sodium hypophosphite, 8-14g/L of sodium acetate and 6-10g/L of borax, and the pH value is 6.5-7.5. The method is applicable to various cement-based piezoelectric composite materials which take piezoelectric ceramic as a functional body and cement and epoxy resin as substrates, the materials are relatively low in cost and relatively good in environmental friendliness, and an obtained plated layer is smooth in surface, uniform and accordant, good in corrosion resistance, good in conductivity and good in weldability, can be solidly combined with the cement-based piezoelectric composite material, and is not easy to drop, good in binding force and very good in application prospect.

The invention discloses a method for chemical nickel-plating on the surface of a cement-based piezoelectric composite. The method comprises the steps of coarsening, reducing, activating and nickel plating. Coarsening is conducted in alkaline coarsening fluid. The applied reducing solution is a sodium borohydride methyl alcohol water solution or a sodium borohydride ethyl alcohol water solution. The applied activating solution is an additive-contained nickel acetate water solution or an additive-contained nickel sulfate water solution. The nickel-plating solution comprises 18-22 g/L of nickel sulfate, 8-16 g/L of trisodium citrate, 26-32 g/L of sodium hypophosphite, 8-14 g/L of sodium acetate and 6-10 g/L of borax, and the pH is 6.5-7.5. The method for chemical nickel-plating on the surface of the cement-based piezoelectric composite is suitable for all kinds of cement-based piezoelectric composites with piezoelectric ceramics as function bodies and cement and epoxy resin as base bodies, the cost is low, and the environmental protection property is better; prepared coatings are flat in surface, uniform, consistent, good in corrosion resistance and electrical conductivity, high in weldability, capable of being closely combined with the cement-based piezoelectric composite, not prone to being disengaged and good in binding force, and application prospects are very good.

The invention relates to a porous polymer ultrasound contrast agent and a preparation method thereof. The preparation method comprises the following steps: S1: dissolving the polylactic-co-glycolic acid in dichloromethane; S2: taking camphor and adding camphor into the dichloromethane solution dissolving the polylactic-co-glycolic acid; S3: performing primary emulsion, specifically adding ammoniumbicarbonate solution into the solution obtained by S2, and performing crushing treatment; S4: performing secondary emulsion, mutually dissolving the solution obtained in S3 and polyvinyl alcohol solution and performing homogenizing; S5: mutually dissolving the solution obtained in S4 and isopropanol solution and performing homogenizing; S6: centrifugally collecting samples and freezing the samples; and S7: performing cell membrane coating, specifically mutually mixing a cell membrane suspension and a finished product obtained in S6 and performing processing by an ultrasonic cleaning machine to obtain a finished product. The beneficial effects are: the contrast agent is stronger, has high compression resistance and stability. Under the mechanical index of conventional ultrasound examination, the contrast agent is not relatively liable to be destroyed, has a long duration of radiography, and the cell membrane coating makes the contrast agent targeted, so the contrast agent can be used as an ultrasound molecular imaging contrast agent.

The invention aims at the chemical industry field, and relates to a preparation method of D,L-2-hydroxy-4-methylthiobutyrate. The method comprises the following steps: fully reacting a hydrocyanic acid gas mixture prepared through an Andrussow method with methylthiopropionaldehyde under the catalysis of an alkali to obtain a 2-hydroxy-4-methylthiobutyronityile reaction system; and mixing the 2-hydroxy-4-methylthiobutyronityile reaction system with alcohol, and carrying out hydrolysis and esterification reactions under the catalysis of an inorganic acid to prepare the D,L-2-hydroxy-4-methylthiobutyrate. Initial raw materials which are not rectified or purified, and are cheap and easily available, an intermediate obtained through a reaction has stable properties, few reaction steps are realized, and a finally obtained product is simply separated and purified to obtain high-purity and high-yield D,L-2-hydroxy-4-methylthiobutyrate.

The invention discloses an outer packaging box for fresh fruits. The outer packaging box comprises a bottom box, a locking bolt, a left cover body, a rubber pad, an ethylene adsorbent and a convex disc, wherein the left cover body is hinged to the surface, close to the left side, of the top of the bottom box; a right cover body is hinged to the surface, close to the right side, of the top of the bottom box; partition plates are welded to the top ends of the inner walls of the left cover body and the right cover body; the partition plates divide the interior of the bottom box into a first chamber and a second chamber from front to back; connecting rods are hinged to the inner walls of one sides of the left cover body and the right cover body; and the other ends of the connecting rods are hinged and fixed to the two sides of the bottom plate. According to the outer packaging box for the fresh fruits, the left cover body and the right cover body are hinged to the two sides of the top of the bottom box, the two sets of partition plates are used in cooperation, when the left cover body and the right cover body cover the box, the two sets of partition plates cover bananas, then the bananas can be placed in the two chambers, the bodies and the roots of the bananas are separated, and the situation that the roots of the bananas emit ethylene, and consequently the whole bananas are mature is effectively avoided.

The invention discloses an environment-friendly preparation method of flexible polyimide heat insulation foam, and a product, and also discloses a preparation method of an aromatic carboxylic ester solution. Fatty alcohol with large steric hindrance, of which carbon atoms are connected with two or more aliphatic hydrocarbon branched chains, reacts with pyromellitic dianhydride in a polar solvent to obtain the low-cost aromatic carboxylate solution which is high in concentration and can be stored for a long time. The prepared carboxylate solution is uniformly mixed with a compound catalyst, a foam stabilizer and a foaming agent to obtain a compound slurry; and isocyanate is quickly and uniformly mixed with the compound slurry to obtain a foamed slurry, the foamed slurry is freely foamed atroom temperature to obtain a polyimide foam intermediate, and the polyimide foam intermediate is subjected to post-curing treatment to obtain the flexible polyimide foam. Low-cost and simple-process preparation of the flexible polyimide heat-insulating foam is achieved, the solvent consumption is greatly reduced, and environmental friendliness in the preparation process is achieved.

The invention belongs to the field of functional polymer materials, and specifically relates to a preparation method of a waterborne epoxy emulsion. The method comprises the following steps: (1) heating one or more epoxy resins and dissolving in a cosolvent; (2) adding phosphoric acid, carrying out a reaction with epoxy resin, and carrying out an open-loop chain extension reaction; (3) adding oneor more alkali compounds, neutralizing resin, and introducing water-borne groups; and (4) adding a large amount of water slowly, and thus obtaining the waterborne epoxy emulsion by phase inversion. According to the preparation method of the self-emulsifying waterborne epoxy emulsion, the emulsion has good stability and can be stored for a long term because the epoxy resin is subjected to direct modification and reversed phase emulsification to form the emulsion; the prepared waterborne epoxy emulsion has good flexibility and high glossiness; the preparation method has the advantages of simplepreparation process, easy operation, high efficiency, low raw material cost, low energy consumption, and environmental protection, and is suitable for industrialized production.